This
is
the
FHIR
R4
Mixed
Normative/Trial
Use
Ballot
#1,
and
the
version
for
the
Cologne
Connectathon
in
May
2018.
The
current
version
is
R3
.
See
the
ballot
introduction
for
details
about
the
ballot.
For
a
full
list
of
available
versions,
see
the
Directory
of
published
versions
and
Timelines
for
an
explanation
of
STU
and
other
statuses.

1.4
FHIR
Core-defined
Extension
Registry

All
extensions
in
this
list
are
defined
under
in
this
specification
and
have
a
base
URI
of
http://hl7.org/fhir/StructureDefinition/
.
Additional
extensions
can
be
registered
on
the
HL7
FHIR
registry
at
http://hl7.org/fhir/registry
.